The present invention is an improvement and operational scanning radiometer for the purpose of determining the spatial distribution of plane radiant temperature in a given space, and as a result thereof it can be used for determining vector radiant temperature as well as asymmetrical aspects of low temperature radiation within such space. More particularly the invention relates to means of determining asymmetrical indoor radiant vectors within an environment and the effect of asymmetrical thermal radiation on thermal comfort of people, plants, animals and other elements within a closed or indoor space. The density of radiant flux crossing a small plane element in space is found to be a vector quantity with both magnitude and direction components. The radiation vector is a measure of the asymmetry of the radiation field, since the radiation vector is defined as a vector whose direction is perpendicular to the plane element in question and whose magnitude is the difference in the radiant flux impinging on opposite sides of the element.
The invention is a method and apparatus for measuring and determining such vectors by means of a new and improved scanning radiometer apparatus and method.